package com.dongwukj.weiwei.net.utils;


import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;

import android.util.Base64;

public class DESUtils {

  public final static String DES_KEY_STRING = "ABSujsuu";

  public static String encrypt(String message, String key) throws Exception {
      Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");

      DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));

      SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
      SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
      IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));
      cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);

      return encodeBase64(cipher.doFinal(message.getBytes("UTF-8")));
  }

  public static String decrypt(String message, String key) throws Exception {

      byte[] bytesrc = decodeBase64(message);convertHexString(message);
      Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
      DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));
      SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
      SecretKey secretKey = keyFactory.generateSecret(desKeySpec);
      IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));

      cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);

      byte[] retByte = cipher.doFinal(bytesrc);
      return new String(retByte);
  }

  public static byte[] convertHexString(String ss) {
      byte digest[] = new byte[ss.length() / 2];
      for (int i = 0; i < digest.length; i++) {
          String byteString = ss.substring(2 * i, 2 * i + 2);
          int byteValue = Integer.parseInt(byteString, 16);
          digest[i] = (byte) byteValue;
      }

      return digest;
  }

  public static String toHexString(byte b[]) {
      StringBuffer hexString = new StringBuffer();
      for (int i = 0; i < b.length; i++) {
          String plainText = Integer.toHexString(0xff & b[i]);
          if (plainText.length() < 2)
              plainText = "0" + plainText;
          hexString.append(plainText);
      }

      return hexString.toString();
  }


  public static String encodeBase64(byte[] b) {
      return Base64.encodeToString(b, Base64.DEFAULT);
  }

  public static byte[] decodeBase64(String base64String) {
      return Base64.decode(base64String, Base64.DEFAULT);
  }
}
